Worried constituents have written to Colne Valley MP Kali Mountford about forthcoming changes.

She said: “Many people with older cars believe their tax will go up to £400 next year.

“This is not true.

“If your car was registered before 2001 and is under 1549cc then car tax will not go up at all.

“If the engine is more than 1549cc your tax will increase from £185 to £200.”

Cars registered after 2001 will be taxed according to their carbon emission.

Ms Mountford added: “Car tax has increased in some cases, but not to the levels widely reported.

“As an example, anyone whose car has a carbon emission rate of 151 grams per kilometre pays £145 in car tax this year will pay £150 next year and £155 the following year.

“If the car is a real gas-guzzler and has an emission rate of 255g/km and above then the tax will rise from £400 to £440 next year and £455 the following year.”

The Labour MP added: “The move to tax cars causing the most pollution took place in 2001 and had the support of all Opposition parties as a way of making motorists aware of the environmental impact of their choice of car.

“This does not mean that people have to swap their family car for a smaller version, but it does mean that they can select a low-emitting vehicle.

“I hope those constituents, who I have also replied to individually, will now feel reassured that they can continue to run their current car.’’